/* Copyright (c) 2001-2025, The HSQL Development Group
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * Neither the name of the HSQL Development Group nor the names of its
 * contributors may be used to endorse or promote products derived from this
 * software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL HSQL DEVELOPMENT GROUP, HSQLDB.ORG,
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */


package org.hsqldb.types;

import java.math.BigDecimal;

import org.hsqldb.OpTypes;
import org.hsqldb.Session;
import org.hsqldb.SessionInterface;
import org.hsqldb.Tokens;
import org.hsqldb.error.Error;
import org.hsqldb.error.ErrorCode;
import org.hsqldb.lib.ArrayUtil;
import org.hsqldb.lib.StringConverter;
import org.hsqldb.lib.StringUtil;

/**
 * Type subclass for CHARACTER, VARCHAR, etc.<p>
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.7.5
 * @since 1.9.0
 */
public class CharacterType extends Type {

    static final int         defaultCharPrecision    = 256;
    static final int         defaultVarcharPrecision = 32 * 1024;
    public static final long maxCharPrecision        = Integer.MAX_VALUE;
    final Collation          collation;
    final Charset            charset;
    final String             nameString;

    public CharacterType(Collation collation, int type, long precision) {

        super(Types.SQL_VARCHAR, type, precision, 0);

        if (collation == null) {
            collation = Collation.getDefaultInstance();
        }

        this.collation  = collation;
        this.charset    = Charset.getDefaultInstance();
        this.nameString = getNameStringPrivate();
    }

    /**
     * Always ASCII collation
     */
    public CharacterType(int type, long precision) {

        super(Types.SQL_VARCHAR, type, precision, 0);

        this.collation  = Collation.getDefaultInstance();
        this.charset    = Charset.getDefaultInstance();
        this.nameString = getNameStringPrivate();
    }

    public CharacterType(String name, long precision) {

        super(Types.SQL_VARCHAR, Types.SQL_VARCHAR, precision, 0);

        this.collation  = Collation.getDefaultInstance();
        this.charset    = Charset.getDefaultInstance();
        this.nameString = name;
    }

    public int displaySize() {
        return precision > Integer.MAX_VALUE
               ? Integer.MAX_VALUE
               : (int) precision;
    }

    public int getJDBCTypeCode() {

        switch (typeCode) {

            case Types.SQL_CHAR :
                return Types.CHAR;

            case Types.SQL_VARCHAR :
                return Types.VARCHAR;

            case Types.SQL_CLOB :
                return Types.CLOB;

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public Class getJDBCClass() {
        return String.class;
    }

    public String getJDBCClassName() {
        return "java.lang.String";
    }

    public int getSQLGenericTypeCode() {
        return typeCode == Types.SQL_CHAR
               ? typeCode
               : Types.SQL_VARCHAR;
    }

    public String getNameString() {
        return nameString;
    }

    private String getNameStringPrivate() {

        switch (typeCode) {

            case Types.SQL_CHAR :
                return Tokens.T_CHARACTER;

            case Types.SQL_VARCHAR :
                return Tokens.T_VARCHAR;

            case Types.SQL_CLOB :
                return Tokens.T_CLOB;

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public String getFullNameString() {

        switch (typeCode) {

            case Types.SQL_CHAR :
                return Tokens.T_CHARACTER;

            case Types.SQL_VARCHAR :
                return "CHARACTER VARYING";

            case Types.SQL_CLOB :
                return "CHARACTER LARGE OBJECT";

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public String getDefinition() {

        if (precision == 0) {
            return getNameString();
        }

        StringBuilder sb = new StringBuilder(32);

        sb.append(getNameString()).append('(').append(precision).append(')');

        return sb.toString();
    }

    public boolean isCharacterType() {
        return true;
    }

    public long getMaxPrecision() {
        return maxCharPrecision;
    }

    public boolean acceptsPrecision() {
        return true;
    }

    public boolean requiresPrecision() {
        return typeCode == Types.SQL_VARCHAR;
    }

    public int precedenceDegree(Type other) {

        if (other.typeCode == typeCode) {
            return 0;
        }

        if (!other.isCharacterType()) {
            return Integer.MIN_VALUE;
        }

        switch (typeCode) {

            case Types.SQL_CHAR :
                return other.typeCode == Types.SQL_CLOB
                       ? 4
                       : 2;

            case Types.SQL_VARCHAR :
                return other.typeCode == Types.SQL_CLOB
                       ? 4
                       : 2;

            case Types.SQL_CLOB :
                return other.typeCode == Types.SQL_CHAR
                       ? -4
                       : -2;

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public Type getAggregateType(Type other) {

        if (other == null) {
            return this;
        }

        if (other == SQL_ALL_TYPES) {
            return this;
        }

        if (typeCode == other.typeCode) {
            return precision >= other.precision
                   ? this
                   : other;
        }

        switch (other.typeCode) {

            case Types.SQL_CHAR :
                return precision >= other.precision
                       ? this
                       : getCharacterType(
                           typeCode,
                           other.precision,
                           other.getCollation());

            case Types.SQL_VARCHAR :
                if (typeCode == Types.SQL_CLOB) {
                    return precision >= other.precision
                           ? this
                           : getCharacterType(
                               typeCode,
                               other.precision,
                               other.getCollation());
                } else {
                    return other.precision >= precision
                           ? other
                           : getCharacterType(
                               other.typeCode,
                               precision,
                               other.getCollation());
                }
            case Types.SQL_CLOB :
                return other.precision >= precision
                       ? other
                       : getCharacterType(
                           other.typeCode,
                           precision,
                           other.getCollation());

            case Types.SQL_BIT :
            case Types.SQL_BIT_VARYING :
            case Types.SQL_BLOB :
            case Types.SQL_BINARY :
            case Types.SQL_VARBINARY :
            case Types.OTHER :
                throw Error.error(ErrorCode.X_42562);

            default :

                /*
                 * @todo - this seems to be allowed in SQL-92 (is in NIST)
                 * but is disallowed in SQL:2003
                 * need to make dependent on a database property
                 */

/*
                int length = other.displaySize();

                return getCharacterType(Types.SQL_VARCHAR,
                                        length).getAggregateType(this);
*/
                throw Error.error(ErrorCode.X_42562);
        }
    }

    /**
     * For concatenation
     */
    public Type getCombinedType(Session session, Type other, int operation) {

        if (operation != OpTypes.CONCAT) {
            return getAggregateType(other);
        }

        Type newType;
        long newPrecision = this.precision + other.precision;

        switch (other.typeCode) {

            case Types.SQL_ALL_TYPES :
                return this;

            case Types.SQL_CHAR :
                newType = this;
                break;

            case Types.SQL_VARCHAR :
                newType = (typeCode == Types.SQL_CLOB)
                          ? this
                          : other;
                break;

            case Types.SQL_CLOB :
                newType = other;
                break;

            default :
                throw Error.error(ErrorCode.X_42562);
        }

        if (newPrecision > maxCharPrecision) {
            if (typeCode == Types.SQL_BINARY) {

                // Standard disallows type length reduction
                // throw Error.error(ErrorCode.X_42570);
                newPrecision = maxCharPrecision;
            } else if (typeCode == Types.SQL_CHAR) {
                newPrecision = maxCharPrecision;
            } else if (typeCode == Types.SQL_VARCHAR) {
                newPrecision = maxCharPrecision;
            }
        }

        return getCharacterType(newType.typeCode, newPrecision, collation);
    }

    public int compare(Session session, Object a, Object b) {
        return compare(session, a, b, OpTypes.EQUAL);
    }

    public int compare(Session session, Object a, Object b, int opType) {

        if (a == b) {
            return 0;
        }

        if (a == null) {
            return -1;
        }

        if (b == null) {
            return 1;
        }

        if (b instanceof ClobData) {
            long lobId = ((ClobData) b).getId();

            return -session.database.lobManager.compare(
                collation,
                lobId,
                (String) a);
        }

        String as = (String) a;
        String bs = (String) b;
        int    la = as.length();
        int    lb = bs.length();

        if (la == lb) {

            //
        } else if (la > lb) {
            if (collation.isPadSpace() && opType != OpTypes.GREATER_EQUAL_PRE) {
                bs = padString(bs, la);
            }
        } else {
            if (collation.isPadSpace() && opType != OpTypes.GREATER_EQUAL_PRE) {
                as = padString(as, lb);
            }
        }

        return collation.compare(as, bs);
    }

    public static String padString(String s, int length) {

        char[] buffer = new char[length];

        s.getChars(0, s.length(), buffer, 0);
        ArrayUtil.fillArray(buffer, s.length(), ' ');

        return String.valueOf(buffer);
    }

    public Object convertToTypeLimits(SessionInterface session, Object a) {

        if (a == null) {
            return a;
        }

        if (precision == 0) {
            return a;
        }

        switch (typeCode) {

            case Types.SQL_CHAR :
            case Types.SQL_VARCHAR : {
                int slen = ((String) a).length();

                if (slen > precision) {
                    if (session instanceof Session) {
                        if (!((Session) session).database.sqlTruncateTrailing) {
                            throw Error.error(ErrorCode.X_22001);
                        }
                    }

                    if (getRightTrimSize((String) a, ' ') <= precision) {
                        return ((String) a).substring(0, (int) precision);
                    } else {
                        throw Error.error(ErrorCode.X_22001);
                    }
                }

                if (typeCode == Types.SQL_VARCHAR) {
                    return a;
                }

                if (slen == precision) {
                    return a;
                }

                char[] b = new char[(int) precision];

                ((String) a).getChars(0, slen, b, 0);

                for (int i = slen; i < precision; i++) {
                    b[i] = ' ';
                }

                return new String(b);
            }

            case Types.SQL_CLOB : {
                ClobData clob = (ClobData) a;

                if (clob.length(session) > precision) {
                    throw Error.error(ErrorCode.X_22001);
                }

                return a;
            }

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public Object castToType(
            SessionInterface session,
            Object a,
            Type otherType) {

        if (a == null) {
            return a;
        }

        return castOrConvertToType(session, a, otherType, true);
    }

    public Object castOrConvertToType(
            SessionInterface session,
            Object a,
            Type otherType,
            boolean cast) {

        switch (otherType.typeCode) {

            case Types.SQL_CHAR :
            case Types.SQL_VARCHAR : {
                int length = ((String) a).length();

                if (precision != 0 && length > precision) {
                    if (StringUtil.rightTrimSize((String) a) > precision) {
                        if (!cast) {
                            throw Error.error(ErrorCode.X_22001);
                        }

                        session.addWarning(Error.error(ErrorCode.W_01004));
                    }

                    a = ((String) a).substring(0, (int) precision);
                }

                switch (typeCode) {

                    case Types.SQL_CHAR :
                        return convertToTypeLimits(session, a);

                    case Types.SQL_VARCHAR :
                        return a;

                    case Types.SQL_CLOB : {
                        ClobData clob = session.createClob(
                            ((String) a).length());

                        clob.setString(session, 0, (String) a);

                        return clob;
                    }

                    default :
                        throw Error.runtimeError(
                            ErrorCode.U_S0500,
                            "CharacterType");
                }
            }

            case Types.SQL_CLOB : {
                long length = ((ClobData) a).length(session);

                if (precision != 0 && length > precision) {

                    // todo nonSpaceLength() not yet implemented for CLOB
                    if (!cast) {
                        throw Error.error(ErrorCode.X_22001);
                    }

                    session.addWarning(Error.error(ErrorCode.W_01004));
                }

                switch (typeCode) {

                    case Types.SQL_CHAR :
                    case Types.SQL_VARCHAR : {
                        if (length > maxCharPrecision) {
                            if (!cast) {
                                throw Error.error(ErrorCode.X_22001);
                            }

                            length = maxCharPrecision;
                        }

                        a = ((ClobData) a).getSubString(
                            session,
                            0,
                            (int) length);

                        return convertToTypeLimits(session, a);
                    }

                    case Types.SQL_CLOB : {
                        if (precision != 0 && length > precision) {
                            return ((ClobData) a).getClob(
                                session,
                                0,
                                precision);
                        }

                        return a;
                    }

                    default :
                        throw Error.runtimeError(
                            ErrorCode.U_S0500,
                            "CharacterType");
                }
            }

            case Types.OTHER :
                throw Error.error(ErrorCode.X_42561);

            case Types.SQL_BLOB :
                long blobLength = ((BlobData) a).length(session);

                if (precision != 0 && blobLength * 2 > precision) {
                    throw Error.error(ErrorCode.X_22001);
                }

                byte[] bytes = ((BlobData) a).getBytes(
                    session,
                    0,
                    (int) blobLength);

                a = StringConverter.byteArrayToHexString(bytes);

                return convertToTypeLimits(session, a);

            case Types.SQL_BIT :
            case Types.SQL_BIT_VARYING :
            case Types.SQL_BINARY :
            case Types.SQL_VARBINARY :
            default :
                String s = otherType.convertToString(a);

                if (precision != 0 && s.length() > precision) {
                    throw Error.error(ErrorCode.X_22001);
                }

                a = s;

                return convertToTypeLimits(session, a);
        }
    }

    public Object convertToType(
            SessionInterface session,
            Object a,
            Type otherType) {

        if (a == null) {
            return a;
        }

        return castOrConvertToType(session, a, otherType, false);
    }

    public Object convertToTypeJDBC(
            SessionInterface session,
            Object a,
            Type otherType) {

        if (a == null) {
            return a;
        }

        if (otherType.typeCode == Types.SQL_BLOB) {
            throw Error.error(ErrorCode.X_42561);
        }

        return convertToType(session, a, otherType);
    }

    /**
     * Relaxes SQL parameter type enforcement, allowing long strings.
     */
    public Object convertToDefaultType(SessionInterface session, Object a) {

        if (a == null) {
            return a;
        }

        String s;

        if (a instanceof Boolean) {
            s = a.toString();
        } else if (a instanceof BigDecimal) {
            s = ((BigDecimal) a).toPlainString();
        } else if (a instanceof Number) {
            s = a.toString();    // use shortcut
        } else if (a instanceof String) {
            s = (String) a;
        } else if (a instanceof java.sql.Date) {
            s = a.toString();
        } else if (a instanceof java.sql.Time) {
            s = a.toString();
        } else if (a instanceof java.sql.Timestamp) {
            s = a.toString();
        } else if (a instanceof java.util.Date) {
            a = new java.sql.Timestamp(((java.util.Date) a).getTime());
            s = a.toString();
        } else if (a instanceof java.util.UUID) {
            s = a.toString();
        } else {
            s = DateTimeType.convertJavaDateTimeObjectToString(a);

            if (s == null) {
                throw Error.error(ErrorCode.X_42561);
            }
        }

        return s;
    }

    public Object convertJavaToSQL(SessionInterface session, Object a) {
        return convertToDefaultType(session, a);
    }

    public String convertToString(Object a) {

        if (a == null) {
            return null;
        }

        switch (typeCode) {

            case Types.SQL_CHAR : {
                int slen = ((String) a).length();

                if (precision == 0 || slen == precision) {
                    return (String) a;
                }

                char[] b = new char[(int) precision];

                ((String) a).getChars(0, slen, b, 0);

                for (int i = slen; i < precision; i++) {
                    b[i] = ' ';
                }

                return new String(b);
            }

            case Types.SQL_VARCHAR : {
                return (String) a;
            }

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public String convertToSQLString(Object a) {

        if (a == null) {
            return Tokens.T_NULL;
        }

        String s = convertToString(a);

        return StringConverter.toQuotedString(s, '\'', true);
    }

    public void convertToJSON(Object a, StringBuilder sb) {

        if (a == null) {
            sb.append("null");

            return;
        }

        StringConverter.toJSONString((String) a, sb);
    }

    public boolean canConvertFrom(Type otherType) {
        return !otherType.isObjectType();
    }

    public int canMoveFrom(Type otherType) {

        if (otherType == this) {
            return 0;
        }

        switch (typeCode) {

            case Types.SQL_VARCHAR : {
                if (otherType.typeCode == typeCode) {
                    return precision >= otherType.precision
                           ? ReType.keep
                           : ReType.check;
                }

                if (otherType.typeCode == Types.SQL_CHAR) {
                    return precision >= otherType.precision
                           ? ReType.keep
                           : ReType.change;
                }

                return -1;
            }

            case Types.SQL_CLOB : {
                if (otherType.typeCode == Types.SQL_CLOB) {
                    return precision >= otherType.precision
                           ? ReType.keep
                           : ReType.check;
                }

                return -1;
            }

            case Types.SQL_CHAR : {
                return otherType.typeCode == Types.SQL_CHAR
                       && precision == otherType.precision
                       ? ReType.keep
                       : ReType.change;
            }

            default :
                return ReType.change;
        }
    }

    public Collation getCollation() {
        return collation;
    }

    public Charset getCharacterSet() {
        return charset;
    }

    /**
     * can add collation and charset equality
     */
    public boolean equals(Object other) {

        if (other == this) {
            return true;
        }

        if (other instanceof CharacterType) {
            return super.equals(other)
                   && ((CharacterType) other).getCollation().equals(
                       getCollation());
        }

        return false;
    }

    public long position(
            SessionInterface session,
            Object data,
            Object otherData,
            Type otherType,
            long offset) {

        if (data == null || otherData == null) {
            return -1L;
        }

        if (otherType.typeCode == Types.SQL_CLOB) {
            long otherLength = ((ClobData) otherData).length(session);

            if (offset + otherLength > ((String) data).length()) {
                return -1;
            }

            if (otherLength > Integer.MAX_VALUE) {
                throw Error.error(ErrorCode.X_22026);
            }

            String otherString = ((ClobData) otherData).getSubString(
                session,
                0,
                (int) otherLength);

            return ((String) data).indexOf(otherString, (int) offset);
        } else if (otherType.isCharacterType()) {
            long otherLength = ((String) otherData).length();

            if (offset + otherLength > ((String) data).length()) {
                return -1;
            }

            return ((String) data).indexOf((String) otherData, (int) offset);
        } else {
            throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    /**
     * length must not be negative
     */
    public static LongPair substringParams(
            long dataLength,
            long start,
            long length,
            boolean hasLength) {

        long end;

        if (hasLength) {
            end = start + length;
        } else {
            end = Math.max(dataLength, start);
        }

        // trim
        if (start >= dataLength || end < 0) {
            start  = 0;
            length = 0;
        } else {
            start  = Math.max(start, 0);
            end    = Math.min(end, dataLength);
            length = end - start;
        }

        return new LongPair(start, length);
    }

    public Object substring(
            SessionInterface session,
            Object data,
            long offset,
            long length,
            boolean hasLength,
            boolean trailing) {

        if (length < 0) {
            throw Error.error(ErrorCode.X_22011);
        }

        long dataLength = typeCode == Types.SQL_CLOB
                          ? ((ClobData) data).length(session)
                          : ((String) data).length();

        if (trailing) {
            offset = dataLength - offset;
        }

        LongPair segment = substringParams(
            dataLength,
            offset,
            length,
            hasLength);

        offset = segment.a;
        length = segment.b;

        if (data instanceof String) {
            return ((String) data).substring(
                (int) offset,
                (int) (offset + length));
        } else if (data instanceof ClobData) {
            if (length > Integer.MAX_VALUE) {
                throw Error.error(ErrorCode.X_22001);
            }

            /* @todo - change to support long strings */
            String result = ((ClobData) data).getSubString(
                session,
                offset,
                (int) length);
            ClobData clob = session.createClob(length);

            clob.setString(session, 0, result);

            return clob;
        } else {
            throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    /**
     * Memory limits apply to Upper and Lower implementations with Clob data
     */
    public Object upper(Session session, Object data) {

        if (data == null) {
            return null;
        }

        if (typeCode == Types.SQL_CLOB) {
            String result = ((ClobData) data).getSubString(
                session,
                0,
                (int) ((ClobData) data).length(session));

            result = collation.toUpperCase(result);

            ClobData clob = session.createClob(result.length());

            clob.setString(session, 0, result);

            return clob;
        }

        return collation.toUpperCase((String) data);
    }

    public Object lower(Session session, Object data) {

        if (data == null) {
            return null;
        }

        if (typeCode == Types.SQL_CLOB) {
            String result = ((ClobData) data).getSubString(
                session,
                0,
                (int) ((ClobData) data).length(session));

            result = collation.toLowerCase(result);

            ClobData clob = session.createClob(result.length());

            clob.setString(session, 0, result);

            return clob;
        }

        return collation.toLowerCase((String) data);
    }

    public Object trim(
            SessionInterface session,
            Object data,
            char trim,
            boolean leading,
            boolean trailing) {

        if (data == null) {
            return null;
        }

        String s;

        if (typeCode == Types.SQL_CLOB) {
            long length = ((ClobData) data).length(session);

            if (length > Integer.MAX_VALUE) {
                throw Error.error(ErrorCode.X_22026);
            }

            s = ((ClobData) data).getSubString(session, 0, (int) length);
        } else {
            s = (String) data;
        }

        int endindex = s.length();

        if (trailing) {
            for (--endindex; endindex >= 0
                             && s.charAt(endindex) == trim; endindex--) {}

            endindex++;
        }

        int startindex = 0;

        if (leading) {
            while (startindex < endindex && s.charAt(startindex) == trim) {
                startindex++;
            }
        }

        /* @todo - change to support long strings */
        if (startindex == 0 && endindex == s.length()) {}
        else {
            s = s.substring(startindex, endindex);
        }

        if (typeCode == Types.SQL_CLOB) {
            ClobData clob = session.createClob(s.length());

            clob.setString(session, 0, s);

            return clob;
        } else {
            return s;
        }
    }

    public Object overlay(
            SessionInterface session,
            Object data,
            Object overlay,
            long offset,
            long length,
            boolean hasLength) {

        if (data == null || overlay == null) {
            return null;
        }

        if (!hasLength) {
            length = typeCode == Types.SQL_CLOB
                     ? ((ClobData) overlay).length(session)
                     : ((String) overlay).length();
        }

        Object temp = concat(
            null,
            substring(session, data, 0, offset, true, false),
            overlay);

        return concat(
            null,
            temp,
            substring(session, data, offset + length, 0, false, false));
    }

    public Object concat(Session session, Object a, Object b) {

        if (a == null || b == null) {
            return null;
        }

        String left;
        String right;

        if (a instanceof ClobData) {
            left = ((ClobData) a).getSubString(
                session,
                0,
                (int) ((ClobData) a).length(session));
        } else {
            left = (String) a;
        }

        if (b instanceof ClobData) {
            right = ((ClobData) b).getSubString(
                session,
                0,
                (int) ((ClobData) b).length(session));
        } else {
            right = (String) b;
        }

        if (typeCode == Types.SQL_CLOB) {
            ClobData clob = session.createClob(left.length() + right.length());

            clob.setString(session, 0, left);
            clob.setString(session, left.length(), right);

            return clob;
        } else {
            return left + right;
        }
    }

    public long size(SessionInterface session, Object data) {

        if (typeCode == Types.SQL_CLOB) {
            return ((ClobData) data).length(session);
        }

        return ((String) data).length();
    }

    /**
     * Matches the string against array containing part strings. Null element
     * in array indicates skip one character. Empty string in array indicates
     * skip any number of characters.
     */
    public Boolean match(Session session, String string, String[] array) {

        if (string == null || array == null) {
            return null;
        }

        String  s      = null;
        int     offset = 0;
        boolean match  = true;

        for (int i = 0; i < array.length; i++) {
            if (array[i] == null) {

                // single char skip
                offset++;

                match = true;
            } else if (array[i].isEmpty()) {

                // string skip
                match = false;
            }

            if (match) {
                if (offset + array[i].length() > string.length()) {
                    return Boolean.FALSE;
                }

                s = string.substring(offset, offset + array[i].length());

                if (collation.compare(s, array[i]) != 0) {
                    return Boolean.FALSE;
                }

                offset += array[i].length();
            } else {
                int index = string.indexOf(array[i], offset);

                if (index < 0) {
                    return Boolean.FALSE;
                }

                offset = index + array[i].length();
                match  = true;
            }
        }

        return Boolean.TRUE;
    }

    public Type getCharacterType(long length) {

        if (length == precision) {
            return this;
        }

        return getCharacterType(this.typeCode, length, this.collation);
    }

    public static int getRightTrimSize(String s, char trim) {

        int endindex = s.length();

        for (--endindex; endindex >= 0
                         && s.charAt(endindex) == trim; endindex--) {}

        endindex++;

        return endindex;
    }

    private static final int fixedTypesLength = 32;
    static CharacterType[]   charArray = new CharacterType[fixedTypesLength];

    static {
        for (int i = 0; i < charArray.length; i++) {
            charArray[i] = new CharacterType(Types.SQL_CHAR, i);
        }
    }

    public static CharacterType getCharacterType(int type, long length) {

        switch (type) {

            case Types.SQL_CHAR :
                if (length < fixedTypesLength) {
                    return charArray[(int) length];
                }

                return new CharacterType(type, (int) length);

            case Types.SQL_VARCHAR :
                return new CharacterType(type, (int) length);

            case Types.SQL_CLOB :
                return new ClobType(length);

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }

    public static CharacterType getCharacterType(
            int type,
            long length,
            Collation collation) {

        if (collation == null) {
            collation = Collation.getDefaultInstance();
        }

        switch (type) {

            case Types.SQL_VARCHAR :
            case Types.SQL_CHAR :
                return new CharacterType(collation, type, (int) length);

            case Types.SQL_CLOB :
                return new ClobType(collation, length);

            default :
                throw Error.runtimeError(ErrorCode.U_S0500, "CharacterType");
        }
    }
}
